A sphere, more fully termed an “armillary sphere”, is an astronomical instrument representing the sky. The name comes from the Latin armilla, “hoop, ring”; the instrument consists of a set of rings, forming the framework of a sphere, with the Earth at its center. The rings represent the ecliptic, tropics, celestial equator, &c, of the sky. The armillary sphere is a period heraldic charge, found in the arms of the Worshipful Company of Joiners, 1571 [Bromley & Child 153].
There is also the “terrestrial sphere”, a globe of the Earth showing the lines of latitude and longitude, and perhaps a vague suggestion of continents. It too is a period charge, found in the crest of Sir Francis Drake, 1581 [Wagner 72].
Finally, there is the “celestial sphere”, showing the constellations and the band of the Zodiac: what the sky would look like from the “outside”, as it were. The celestial sphere is found in the crest of Bull, watchmaker to Elizabeth I [Parker 547].
Brian Caradoc Walsh bears: Gules ermined, an armillary sphere Or.
Romas the Mapmaker bears: Per fess gules mullety Or and vert, a dance and in base a terrestrial sphere Or.
Aurelia Saturnina bears: Purpure, a celestial sphere argent between three bees proper.